Vegetable wax



' many special uses.

Patented Mar. 11, 1941 UNITED STATES PATENT OFFICE.

VEGETABLE (AX No Drawing. Application April 26, 1940, Serial No. 331,806

6 Claims.

This invention relates to a process for manufacturing wax and deals,more specifically, with a process for manufacturing a vegetable wax ofsatisfactory lightness of color from crude vegetable wax powder.

Many vegetable waxes such as carnauba wax, esparto grass wax, sugar canewax and ouricury wax are obtained from the plants by means ofmechanically removing the wax from the plant leaves and/or stems. Thepowder so obtained is herein referred to as crude wax powder and iscomposed of small particles of pure wax together with particles ofvegetable matter of like size.

A brief description of the manufacture of carnauba wax from its crudepowder will illustrate the methods heretofore employed in processing acrude wax powder to obtain the raw material wax. The carnauba wax powderis obtained by thoroughly beating the dried carnauba palm leaves. Thispowder contains leafy material and other non-waxy matter which may equalas much as 20% of the total mass of the powder. The wax is separatedfrom the leafy material and other non-waxy matter by heating the powderin pots over an open fire to a temperature above the melting point ofthe wax and crudely straining the molten mass through a cloth. Themolten wax filtrate, upon cooling, forms the dark green, brown orbrownish black raw material carnauba wax of commerce. The term rawmaterial wax refers to the wax cakes obtained after the first melting ofthe wax powder.

The untreated dark colored wax is not suited for many of the commercialuses of this wax without subjecting it to costly bleaching treatments.Many such bleaching treatments have been proposed and they may beclassified generally as those employing adsorbents; those employingoxidizing and reducing agents, and those which combine both adsorbentsand the chemical agents. While the bleaching with adsorbents, such asadsorbent clay or carbon, is satisfactory for many commercial purposes,it does not produce a wax of sufficient lightness of color for Thebleaching methods which employ chemicals as bleaching agents oftenprovide a wax product of satisfactory lightness of color, but thechemical action required therefor also alters the structural andchemical nature of the original wax to an extent which interferes withthose uses of the wax which depend on the chemical and structuralcharacteristics of the original wax.

It is therefore an important object of this invention to provide aprocess for manufacturing a of the raw material wax cakes.

raw material vegetable wax from its crude powder which is ofsatisfactory lightness of color for all commercial purposes. Anotherobject of this invention is to provide a process for manufacturing a waxfrom vegetable wax powder which is of satisfactory lightness of colorand contains the chemically and structurally unaltered components of theoriginal wax. A further object of this invention is to provide aneconomical process for manufacturing a light-colored wax from crudevegetable wax powder.

Raw material wax as heretofore produced contains appreciable quantitiesof resinous matter which is highl undesirable in many of the commercialuses of the wax. This resinous or gummy matter cannot be satisfactorilyremoved according to the bleaching treatments or commercial purificationprocesses heretofore proposed. It is therefore a further object of thisinvention to provide a process for manufacturing raw material wax fromvegetable wax powder which produces a wax substantially resin free.Other objects will readily appear from the description of the inventionhereinafter set forth.

It has heretofore been thought that the dark coloration of the rawmaterial wax cakes obtained from vegetable wax powder was inherentwithin the components of the wax itself. We have discovered that thepure wax particles in the wax powder will form a light colored wax whenmechanically separated from the non-wax matter under a microscope. Wediscovered further that the undesirable deep coloration of the rawmaterial is introduced into the wax by virtue of the melting of the waxin the presence of the leafy material and other non-waxy matter. Part ofthe coloration is obtained from sources other than leafy matter, such assand, clay, dirt and humus material, but this coloration can readily besatisfactorily removed from the wax cake by means of subsequent remeltinand filtration. The leafy matter, however, contains diiiicultlyremovable high coloring substances, such as chlorophyll and xanthophyll,which, together with their decomposition products and the decompositionproducts of other color-forming substances, are extracted by the hotmolten wax to form the greater part of the undesirable deep colorationThis coloration is thereby so thoroughly incorporated within the waxthat its subsequent complete removal has not been attained by any knownprocess whereby the product produced retains the components of theoriginal wax unchanged.

Contrary to the teachings of the art, we have discovered a processwhereby a light colored wax is obtained from wax powder withoutbleaching the wax. Our process comprises the removal of the coloring andcolor-forming substances from the wax powder composed of wax and leafyparticles, prior to the separation of the wax from the non-waxy matter.This removal of coloring substances is accomplished by means of suitablesolvents. Any solvent which readily dissolves chlorophyll, xanthophylland like substances found in dried leaf tissue, but which does notdissolve appreciable quantities of wax, may be employed in our process.We find that the oxygenated solvents are best suited for this purpose,such as alcohols, ketones, esters and ethers, and that ethyl alcohol isthe preferred solvent.

As the first step of our process, the wax powder is placed in the kettleand the cold solvent is added thereto. The amount of solvent employeddepends on the type of wax powder, the percentage of leafy matter insuch powder, and the quality of wax desired. We found that with carnaubawax powder, a good quality wax is obtained when using about five partsof ethyl alcohol to one part of powder and steeping the powder andsolvent for about 12 hours. An exceptionally fine quality wax isproduced with the same powder when using about 20 parts of solvent toone part of powder and steeping for a period of about 48 hours. We foundthat it was preferable to add the solvent in half, quarter or lesserportions and allow each such portion to steep for a period of from 6 to48 hours. In adding the solvent in two or more steps, each portion ofsolvent is removed before adding more solvent.

After the final removal of the solvent from the powder by filtration orother suitable means, the filter cake, composed of wax particles andfinely decolorized leafy particles, is treated further to remove allpossible solvent therefrom. Mechanical presses may be employed for thispurpose, but the best results are obtained by blowing air through thefilter cake. The filter cake is then placed in a still and heated to atemperature sufiicient to melt the wax and drive off substantially allof the remaining solvent. The molten mixture is filtered to remove theleafy and other non-waxy matter and the molten wax filtrate, uponcooling, forms wax cakes of satisfactory lightness of color.

Certain uses of vegetable waxes demand a product of very light colorfree from resinous matter and all traces of the steeping solventemployed in the manufacture or bleaching of wax cakes. It has been foundthat the addition of a suitable adsorbent to the wax powder filter cake,such as adsorbent clays or carbons, prior to the heating anddistillation step in the above process, effectively removes the resinousmatter and the last traces of solvent and thereby provides a wax productof exceptional purity and lightness of color. The adsorbent serves thefurther purpose of facilitaing the large scale filtration of the moltenwax in the presence of finely divided leafy material.

The following procedure is given as an example of our process:

100 grams of carnauba wax powder was placed in a beaker with 500 c. c.of cold ethyl alcohol and allowed to steep for six hours. The alcoholwas then drawn off and another like portion was added to the powder andsteeped for another six hours. The slurry of alcohol and powder wasfiltered and the filter cake pressed to remove all possible solvent. Thefilter cake was then placed in a still together with grams of adsorbentclay and heated sufiiciently to melt the wax and drive off the residualalcohol. The molten. residue in the still was filtered to remove theadsorbent and other non-waxy matter, and the molten wax filtrate, uponcooling, solidified to form wax cakes of satisfactory lightness ofcolor.

Although the application of our process has been set forth withreference to carnauba wax powder, no limitation is thereby imposed onthe process in that it is applicable generally to the manufacture of allvegetable waxes which are obtained from the plants in the form of apowder.

As many apparently widely different embodiments of this invention may bemade without departing from the spirit or scope thereof, it isunderstood that we do not limit ourselves to the specific embodimentthereof except as defined in the appended claims.

We claim:

1. The method of manufacturing raw material wax cakes from vegetable waxpowder which comprises steeping the wax powder in a solvent capable ofdissolving chlorophyl, removing the solvent from the wax powder, heatingthe powder to a temperature above the melting point of the wax,filtering the resulting molten mass to remove the leafy material andcooling the filtrate.

2. The method of manufacturing raw material wax cakes from vegetable waxpowder which comprises steeping the wax powder in a solvent capable ofdissolving chlorophyl, removing the solvent from the wax powder, addinga suitableadsorbent thereto, heating to a temperature above the meltingpoint of the wax, filtering and cool ing the filtrate.

3. In the art of manufacturing solid wax cakes from vegetable waxpowder, the step which comprises steeping the vegetable wax powder in asolvent capable of dissolving chlorophyl and removing such solvent fromthe wax powder prior to the initial melting of the wax.

4. The method of manufacturing raw material carnauba wax from thecarnauba wax powder which comprises steeping the wax powder in a solventcapable of dissolving chlorophyl, removing the solvent from the waxpowder, heating the powder to a temperature above the melting point ofthe wax, filtering the resulting molten mass to remove the leafymaterial and cooling the filtrate.

5. The method of manufacturing raw material carnauba wax from carnaubawax powder which comprises steeping the wax powder in a solvent capableof dissolving chlorophyl, removing the solvent from the wax powder,adding a suitable adsorbent thereto, heating to a temperature above themelting point of the wax, filtering and cooling the filtrate.

6. In the art of manufacturing raw material carnauba wax, the step whichcomprises steeping the carnauba wax powder in a solvent capable ofdissolving chlorophyl and removing such solvent prior to the initialmelting of the wax.

JOHN VERNON STEINLE. ELBERT S. MCLOUD.

